No reaction after Logging to the webinterface

Dear Sir or Madam,

my System is:
owncloud 3.13.0-74
php: 5.5.9
ubuntu 14.04.4 LTS

Now i have a problem with the webinterface. When i try to logging in the webinterface no reaction is comming.
The Username and Password is correct. When i test in the owncloud vmdk cmd konsole the logging is successfully.
but I cannot logging in the webinterface. THe webinterface have no reaction nothing.
I dont know what is the Problem?

Make sure that you are running a current OC version. Currently supported are 8.0.x, 8.1.x, 8.2.x, 9.0.x, and 9.1.x. Furthermore, if you experience such issues, we need your logfiles to help you.

Im so sorry i am not an Linux Profi. How can i find the log files?
THX

Hi,

if you would have a look at the template shown when creating a new thread (which starts with Please help us by providing the following info.) and have filled out the issue template in your initial post as asked in https://central.owncloud.org/t/webinterface-root-login-failed/2691/7?u=realrancor you would already have found that info.

Additionally you would save the people in here a lot of time when doing so as they need to ask for such stuff which you actually could have provided in your initial post.